#!/usr/bin/env python # SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD # SPDX-License-Identifier: Apache-2.0 from typing import List, Optional from construct import Const, Int32ul, Struct from fatfsgen import FATFS from fatfsgen_utils.exceptions import WLNotInitialized from fatfsgen_utils.utils import crc32, generate_4bytes_random, get_args_for_partition_generator class WLFATFS: # pylint: disable=too-many-instance-attributes CFG_SECTORS_COUNT = 1 DUMMY_SECTORS_COUNT = 1 WL_CONFIG_HEADER_SIZE = 48 WL_STATE_RECORD_SIZE = 16 WL_STATE_HEADER_SIZE = 64 WL_STATE_COPY_COUNT = 2 UINT32_MAX = 4294967295 WL_SECTOR_SIZE = 0x1000 WL_STATE_T_DATA = Struct( 'pos' / Int32ul, 'max_pos' / Int32ul, 'move_count' / Int32ul, 'access_count' / Int32ul, 'max_count' / Int32ul, 'block_size' / Int32ul, 'version' / Int32ul, 'device_id' / Int32ul, 'reserved' / Const(28 * b'\x00') ) WL_CONFIG_T_DATA = Struct( 'start_addr' / Int32ul, 'full_mem_size' / Int32ul, 'page_size' / Int32ul, 'sector_size' / Int32ul, 'updaterate' / Int32ul, 'wr_size' / Int32ul, 'version' / Int32ul, 'temp_buff_size' / Int32ul ) WL_CONFIG_T_HEADER_SIZE = 48 def __init__(self, size: int = 1024 * 1024, reserved_sectors_cnt: int = 1, fat_tables_cnt: int = 1, sectors_per_cluster: int = 1, sector_size: int = 0x1000, sectors_per_fat: int = 1, explicit_fat_type: int = None, hidden_sectors: int = 0, long_names_enabled: bool = False, entry_size: int = 32, num_heads: int = 0xff, oem_name: str = 'MSDOS5.0', sec_per_track: int = 0x3f, volume_label: str = 'Espressif', file_sys_type: str = 'FAT', version: int = 2, temp_buff_size: int = 32, update_rate: int = 16, device_id: int = None, root_entry_count: int = 512, media_type: int = 0xf8) -> None: if sector_size != WLFATFS.WL_SECTOR_SIZE: raise NotImplementedError(f'The only supported sector size is currently {WLFATFS.WL_SECTOR_SIZE}') self._initialized = False self.sector_size = sector_size self._version = version self._temp_buff_size = temp_buff_size self._device_id = device_id self._update_rate = update_rate self.partition_size = size self.total_sectors = self.partition_size // self.sector_size self.wl_state_size = WLFATFS.WL_STATE_HEADER_SIZE + WLFATFS.WL_STATE_RECORD_SIZE * self.total_sectors # determine the number of required sectors (roundup to sector size) self.wl_state_sectors = (self.wl_state_size + self.sector_size - 1) // self.sector_size self.boot_sector_start = self.sector_size # shift by one "dummy" sector self.fat_table_start = self.boot_sector_start + reserved_sectors_cnt * self.sector_size wl_sectors = WLFATFS.DUMMY_SECTORS_COUNT + WLFATFS.CFG_SECTORS_COUNT + self.wl_state_sectors * 2 self.plain_fat_sectors = self.total_sectors - wl_sectors self.plain_fatfs = FATFS( explicit_fat_type=explicit_fat_type, size=self.plain_fat_sectors * self.sector_size, reserved_sectors_cnt=reserved_sectors_cnt, fat_tables_cnt=fat_tables_cnt, sectors_per_cluster=sectors_per_cluster, sector_size=sector_size, sectors_per_fat=sectors_per_fat, root_entry_count=root_entry_count, hidden_sectors=hidden_sectors, long_names_enabled=long_names_enabled, entry_size=entry_size, num_heads=num_heads, oem_name=oem_name, sec_per_track=sec_per_track, volume_label=volume_label, file_sys_type=file_sys_type, media_type=media_type ) self.fatfs_binary_image = self.plain_fatfs.state.binary_image def init_wl(self) -> None: self.fatfs_binary_image = self.plain_fatfs.state.binary_image self._add_dummy_sector() # config must be added after state, do not change the order of these two calls! self._add_state_sectors() self._add_config_sector() self._initialized = True def _add_dummy_sector(self) -> None: self.fatfs_binary_image = self.sector_size * b'\xff' + self.fatfs_binary_image def _add_config_sector(self) -> None: wl_config_data = WLFATFS.WL_CONFIG_T_DATA.build( dict( start_addr=0, full_mem_size=self.partition_size, page_size=self.sector_size, sector_size=self.sector_size, updaterate=self._update_rate, wr_size=16, version=self._version, temp_buff_size=self._temp_buff_size ) ) crc = crc32(list(wl_config_data), WLFATFS.UINT32_MAX) wl_config_crc = Int32ul.build(crc) # adding three 4 byte zeros to align the structure wl_config = wl_config_data + wl_config_crc + Int32ul.build(0) + Int32ul.build(0) + Int32ul.build(0) self.fatfs_binary_image += (wl_config + (self.sector_size - WLFATFS.WL_CONFIG_HEADER_SIZE) * b'\xff') def _add_state_sectors(self) -> None: wl_state_data = WLFATFS.WL_STATE_T_DATA.build( dict( pos=0, max_pos=self.plain_fat_sectors + WLFATFS.DUMMY_SECTORS_COUNT, move_count=0, access_count=0, max_count=self._update_rate, block_size=self.sector_size, version=self._version, device_id=self._device_id or generate_4bytes_random(), ) ) crc = crc32(list(wl_state_data), WLFATFS.UINT32_MAX) wl_state_crc = Int32ul.build(crc) wl_state = wl_state_data + wl_state_crc self.fatfs_binary_image += WLFATFS.WL_STATE_COPY_COUNT * ( (wl_state + (self.sector_size - WLFATFS.WL_STATE_HEADER_SIZE) * b'\xff') + ( self.wl_state_sectors - 1) * self.sector_size * b'\xff') def wl_write_filesystem(self, output_path: str) -> None: if not self._initialized: raise WLNotInitialized('FATFS is not initialized with WL. First call method WLFATFS.init_wl!') with open(output_path, 'wb') as output: output.write(bytearray(self.fatfs_binary_image)) def wl_generate(self, input_directory: str) -> None: """ Normalize path to folder and recursively encode folder to binary image """ self.plain_fatfs.generate(input_directory=input_directory) def wl_create_file(self, name: str, extension: str = '', path_from_root: Optional[List[str]] = None) -> None: self.plain_fatfs.create_file(name, extension, path_from_root) def wl_create_directory(self, name: str, path_from_root: Optional[List[str]] = None) -> None: self.plain_fatfs.create_directory(name, path_from_root) def wl_write_content(self, path_from_root: List[str], content: bytes) -> None: self.plain_fatfs.write_content(path_from_root, content) if __name__ == '__main__': desc = 'Create a FAT filesystem with support for wear levelling and populate it with directory content' args = get_args_for_partition_generator(desc) wl_fatfs = WLFATFS(sector_size=args.sector_size, sectors_per_cluster=args.sectors_per_cluster, size=args.partition_size, root_entry_count=args.root_entry_count, explicit_fat_type=args.fat_type) wl_fatfs.wl_generate(args.input_directory) wl_fatfs.init_wl() wl_fatfs.wl_write_filesystem(args.output_file)